Apparatus for developing and fixing photographic plates or films in daylight.



PATBN'IED JAN. 3, 1905.

S. HALL & 0. ZWIEBACK. APPARATUS FOR DEVELOPING AND FIXING PHOTOGRAPHIG PLATES OR FILMS IN DAYLIGHT.

APPLICATION FILED APR. 27. 1904.

Fly. 3

WITNESSES ATTORNEYS I trough.

UNITED STATES Patented January 3, 1905.

PATENT 'UEETCE.

SYDNEY HALL AND OSCAR ZWIEBACK, OF FRANKFORT-ON-TI-IE-MAIN, GERMANY.

APPARATUS FOR DEVELOPING AND FIXING PHOTOGRAPHIC PLATES OR FILMS IN DAYLIGHT.

SPECIFICATION forming part of Letters Patent N0. 779,217, dated January 3, 1905.

D Application filed April 2'7, 190A. Serial No. 205,199.

To (LU whom it may concern.-

Be it known that we, SYDNEY HALL, engineer, of 22 Eschenheimer Landstrasse, and OSCAR ZWIEBAOK, of 4:6 Moselstrasse, Frankfort-on-the-lIain, Germany, have invented a new and useful Improvement in Apparatus for Developing and FixingPhotographic Plates 0r Films in Daylight; and we do hereby declare the following to be a full, clear, and exact description of the same.

The subject-matter of the present invention is an apparatus for developing and fixing photographic plates, films, or the like in full dayli ht or any other light and which is in the form of a fiat dark slide and of dimensions very little in excess of the dimensions of the plate, thus affording the material advantage of particular convenience and utility. Observation of the progress of development in the apparatus is facilitated by fitting the apparatus on its two side faces with a non-actinic and a colorless glass pane, respectively, the latter of which can be screened of? by a slide. At the back of the apparatus a hood is attached, so as to prevent access of light when examining the progress of development. The insertion of the plate into the apparatus is effected by means of a changing-bag, the plate being introduced through one of the narrow sides of the apparatus which is fitted with a tightly-closing cover. The three other sides of the apparatus are formed by a tube which communicates through holes with the interior of the apparatus and which is provided with two orifices, which can be tightly closed, for pouring liquid into the interior of the box or This arrangement permits the introduction of liquid without any access of light, and as the surface of the plate is covered rapidly and throughout by the liquid the development will be effected without any streaks or spots. It is also to increase the strength of the bath by adding more of the developer as the mixing of the liquids ensues in the fran1- ing-tube before they enter the developingchamber of the appliance. In order to watch the developing process, the operator introduces his head into the screening-hood and pulls out the dark slide. The process can be l watched very minutely by looking through the glass faces of the apparatus, one being colorless and the other red glass, while in looking through two sheets of red glass, as in ordinary photographic appliances, only a very imperfect observation is possible, which,nioreover, can only take place in subdued daylight.

In the appended drawings, illustrating one form of the invention, Figure 1 shows an elevation in section with cover closed; and Fig. 2 shows a plan also in section, the section beingtaken upon the line A B. Fig. 3 is a front view of the right side of the apparatus.

As seen from the drawings, the three closed narrow sides of the apparatus are formed by a tube the end of which is closed by the side piece 7), which is provided for the purpose of introducing the plate with a slot 0, which can be closed by a cover (Z, arranged to swing back on hinges and closing tightly down on an india-rubber hearing or packing f, being then secured by a suitable fastening. The back of this box-like arrangement is formed by a sheet of non-actinic' glass it and the front by a colorless glass pane i, both bearing against the inner frame 5. The sheet of clear glass can be screened by means of a slide 7'. The extreme position of the slide when drawn out is determined by a fillet on the said slide, which comes into contact with the edge of the lower part of the frame Z in order to prevent the slide from being drawn entirely out of the apparatus. In the tube a there are formed two orifices a n which can be closed by screws 122/ m which are provided for pouring the liquid in and letting the air which is displaced by the liquid escape. The communication between the tube a and the interior compartment is established by two rows of holes, of which one (marked 0) is arranged in the end of the limb of the tube which has no orifices for introducing liquid next to the clear glass, while the other row, 0 is in the opposite half of the other limb of the tube next to the red glass pane. At the back of the apparatus a light-proof hood 2) is attached by means of a frame qfor purposes of observation, the frame 9 being inserted between two fixed clips 9* 1' and one spring-clip 0 In use a plate is introduced into the apparatus, the screws closing the orifices n and a are detached, and the apparatus is placed in a horizontal position. The developer is then pouredv in through the orifice n and enters the developing-compartment through the holes 0, and by reason of the smallness of the interior space the whole surface of the plate is immediately covered by the liquid, so that there can be no marking of the plate. The air displaced by the liquid poured in escapes through the holes 0 toward the orifice n As soon as liquid appears at the orifice a the apparatus is completely filled. Thereupon the orifices n and n are reclosed by the screws. In order to watch the development, the hood 3) is attached to the apparatus, and the operator introduces his head into the hood and withdraws slide 1'. When the development is completed, slide y' is pushed in again and the liquid is discharged through the orifice 92/. The same proceeding as in developing is to be adopted in the subsequent fixing and washing of the plates. This arrangement, moreover, permits of the strength of the bath to be regulated without interfering with the process of development, as the added liquid will in the first place mix with the weaker liquid in the tube a before passing through the holes 0 into the interior compartment.

Having now particularly described and ascertained the nature of our said invention and in what manner the same is to be performed, We declare that what we claim, and desire to secure by Letters Patent, is

1. A developing and fixing apparatus, comprising a slide having a face of non-actinic and an opposite face of colorless glass, a tube partially surrounding said slide and having an inlet and outlet therein, means for supplying liquid from said tube to the interior of said slide, and means for preventing the access of light to said face of colorless glass.

2. A developing and fixing apparatus, comprising a slide having a face of non-actinic and an opposite face of colorless glass, a side piece provided with a slot for the insertion of a photographic plate, a tube surrounding the remaining sides of said slide, said tube having an inlet and outlet therein and means for supplying liquid to' the interior of said slide, and means for preventing the access of light to said face of colorless glass.

3. A developing and fixing apparatus, comprising a slide having a side piece provided with a slot for inserting a photographic plate,

and a U-shaped tube surrounding the remaining sides of said slide and having closed ends abutting the ends of said side piece, said tube having an inlet and outlet and being provided with means for supplying liquid therefrom to the interior of said slide.

4. In adeveloping and fixing apparatus, the combination, with a 'slide having an opening for the insertion of a photographic plate, of a U-shaped tube partially surrounding said slide, one leg of said tube being provided with an inlet and outlet and with openingsin the lower portion thereof, said openings communicating with the interior of said slide, while the other leg of said tube is provided with openings in its upper portion also communicating with the interior of said slide.

5. Ina developing and fixing apparatus, the combination, with a slide having a face of nonactinic and an opposite face of colorless glass, of a U-shaped tube partiallysurrounding said slide, each leg of said tube being provided; with openings for supplying liquid to the interior of said slide.

6. In a developing and fixing apparatus, the combination, with a slide having a face of nonaetinic and an opposite face of colorless glass, of a tube partially surrounding said slide and having an inlet and outlet therein, said tube having two sets of openings for supplying liquid to the interior of said slide, one set be ing adjacent to the face of non-actinic glass and the other set being adjacent to the face of colorless glass.

7. In a developing and fixing apparatus, the combination, with a slide having a face of nonactinic and an opposite face of colorless glass, of means for supplying liquid to the interior of said slide, and a sliding plate for covering said face of colorless glass.

8. A developing and fixing apparatus comprising a slide having a face of non-actinic and an opposite face of colorless glass, means for supplying liquid to the interior of said slide, and a sliding plate and hood for pre venting the access of light to said face of colorless glass.

In testimony that we claim the foregoing as our invention we have signed our names in presence of two subscribing witnesses.

SYDNEY HALL. OSCAR ZWIEBACK.

I/Vitnesses:

JEAN GRUND, CARL GRUND. 

